Refactor (windows).

color_windows.go

@@ -42,14 +42,11 @@ func selectColor(opts options) (color.Color, error) {
 	}
 
 	defer setup()()
-
+	unhook, err := hookDialog(opts.ctx, opts.windowIcon, opts.title, nil)
-	if opts.ctx != nil || opts.title != nil {
+	if err != nil {
-		unhook, err := hookDialog(opts.ctx, opts.windowIcon, opts.title, nil)
+		return nil, err
-		if err != nil {
-			return nil, err
-		}
-		defer unhook()
 	}
+	defer unhook()
 
 	ok := win.ChooseColor(&args)
 	if opts.ctx != nil && opts.ctx.Err() != nil {

entry_windows.go

@@ -163,7 +163,7 @@ func entryProc(wnd win.HWND, msg uint32, wparam uintptr, lparam *unsafe.Pointer)
 		default:
 			return 1
 		case win.IDOK, win.IDYES:
-			dlg.out = getWindowString(dlg.editCtl)
+			dlg.out = win.GetWindowText(dlg.editCtl)
 		case win.IDCANCEL:
 			dlg.err = ErrCanceled
 		case win.IDNO:

file_windows.go

@@ -37,14 +37,11 @@ func selectFile(opts options) (string, error) {
 	args.InitialDir, args.DefExt = initDirNameExt(opts.filename, res[:])
 
 	defer setup()()
-
+	unhook, err := hookDialog(opts.ctx, opts.windowIcon, nil, nil)
-	if opts.ctx != nil {
+	if err != nil {
-		unhook, err := hookDialog(opts.ctx, opts.windowIcon, nil, nil)
+		return "", err
-		if err != nil {
-			return "", err
-		}
-		defer unhook()
 	}
+	defer unhook()
 
 	ok := win.GetOpenFileName(&args)
 	if opts.ctx != nil && opts.ctx.Err() != nil {
@@ -83,14 +80,11 @@ func selectFileMultiple(opts options) ([]string, error) {
 	args.InitialDir, args.DefExt = initDirNameExt(opts.filename, res[:])
 
 	defer setup()()
-
+	unhook, err := hookDialog(opts.ctx, opts.windowIcon, nil, nil)
-	if opts.ctx != nil {
+	if err != nil {
-		unhook, err := hookDialog(opts.ctx, opts.windowIcon, nil, nil)
+		return nil, err
-		if err != nil {
-			return nil, err
-		}
-		defer unhook()
 	}
+	defer unhook()
 
 	ok := win.GetOpenFileName(&args)
 	if opts.ctx != nil && opts.ctx.Err() != nil {
@@ -160,14 +154,11 @@ func selectFileSave(opts options) (string, error) {
 	args.InitialDir, args.DefExt = initDirNameExt(opts.filename, res[:])
 
 	defer setup()()
-
+	unhook, err := hookDialog(opts.ctx, opts.windowIcon, nil, nil)
-	if opts.ctx != nil {
+	if err != nil {
-		unhook, err := hookDialog(opts.ctx, opts.windowIcon, nil, nil)
+		return "", err
-		if err != nil {
-			return "", err
-		}
-		defer unhook()
 	}
+	defer unhook()
 
 	ok := win.GetSaveFileName(&args)
 	if opts.ctx != nil && opts.ctx.Err() != nil {
@@ -231,7 +222,7 @@ func pickFolders(opts options, multi bool) (string, []string, error) {
 		}
 	}
 
-	if opts.ctx != nil {
+	if opts.ctx != nil || opts.windowIcon != nil {
 		unhook, err := hookDialog(opts.ctx, opts.windowIcon, nil, nil)
 		if err != nil {
 			return "", nil, err
@@ -302,7 +293,7 @@ func browseForFolder(opts options) (string, []string, error) {
 		args.CallbackFunc = syscall.NewCallback(browseForFolderCallback)
 	}
 
-	if opts.ctx != nil {
+	if opts.ctx != nil || opts.windowIcon != nil {
 		unhook, err := hookDialog(opts.ctx, opts.windowIcon, nil, nil)
 		if err != nil {
 			return "", nil, err

internal/win/user32.go

@@ -268,6 +268,13 @@ func GetWindowThreadProcessId(hwnd HWND, pid *uint32) (tid uint32, err error) {
 	return windows.GetWindowThreadProcessId(hwnd, pid)
 }
 
+func GetWindowText(wnd HWND) string {
+	len, _ := getWindowTextLength(wnd)
+	buf := make([]uint16, len+1)
+	getWindowText(wnd, &buf[0], len+1)
+	return syscall.UTF16ToString(buf)
+}
+
 func SendMessagePointer(wnd HWND, msg uint32, wparam uintptr, lparam unsafe.Pointer) (ret uintptr) {
 	r0, _, _ := syscall.Syscall6(procSendMessageW.Addr(), 4, uintptr(wnd), uintptr(msg), uintptr(wparam), uintptr(lparam), 0, 0)
 	ret = uintptr(r0)
@@ -389,16 +396,15 @@ type CWPRETSTRUCT struct {
 //sys DestroyWindow(wnd HWND) (err error) = user32.DestroyWindow
 //sys DispatchMessage(msg *MSG) (ret uintptr) = user32.DispatchMessageW
 //sys EnableWindow(wnd HWND, enable bool) (ok bool) = user32.EnableWindow
-//sys EnumChildWindows(parent HWND, enumFunc uintptr, lparam unsafe.Pointer) = user32.EnumChildWindows
 //sys EnumWindows(enumFunc uintptr, lparam unsafe.Pointer) (err error) = user32.EnumChildWindows
-//sys GetDlgCtrlID(wnd HWND) (ret int) = user32.GetDlgCtrlID
+//sys GetDlgItem(dlg HWND, dlgItemID int) (ret HWND, err error) = user32.GetDlgItem
 //sys getDpiForWindow(wnd HWND) (ret int) = user32.GetDpiForWindow
 //sys GetMessage(msg *MSG, wnd HWND, msgFilterMin uint32, msgFilterMax uint32) (ret uintptr) = user32.GetMessageW
 //sys GetSystemMetrics(index int) (ret int) = user32.GetSystemMetrics
 //sys GetWindowDC(wnd HWND) (ret Handle) = user32.GetWindowDC
 //sys GetWindowRect(wnd HWND, cmdShow *RECT) (err error) = user32.GetWindowRect
-//sys GetWindowText(wnd HWND, str *uint16, maxCount int) (ret int, err error) = user32.GetWindowTextW
+//sys getWindowText(wnd HWND, str *uint16, maxCount int) (ret int, err error) = user32.GetWindowTextW
-//sys GetWindowTextLength(wnd HWND) (ret int, err error) = user32.GetWindowTextLengthW
+//sys getWindowTextLength(wnd HWND) (ret int, err error) = user32.GetWindowTextLengthW
 //sys IsDialogMessage(wnd HWND, msg *MSG) (ok bool) = user32.IsDialogMessageW
 //sys LoadIcon(instance Handle, resource uintptr) (ret Handle, err error) = user32.LoadIconW
 //sys LoadImage(instance Handle, name *uint16, typ int, cx int, cy int, load int) (ret Handle, err error) = user32.LoadImageW
@@ -406,6 +412,7 @@ type CWPRETSTRUCT struct {
 //sys RegisterClassEx(cls *WNDCLASSEX) (err error) = user32.RegisterClassExW
 //sys ReleaseDC(wnd HWND, dc Handle) (ok bool) = user32.ReleaseDC
 //sys SendMessage(wnd HWND, msg uint32, wparam uintptr, lparam uintptr) (ret uintptr) = user32.SendMessageW
+//sys SetDlgItemText(dlg HWND, dlgItemID int, str *uint16) (err error) = user32.SetDlgItemTextW
 //sys SetFocus(wnd HWND) (ret HWND, err error) = user32.SetFocus
 //sys SetForegroundWindow(wnd HWND) (ok bool) = user32.SetForegroundWindow
 //sys setThreadDpiAwarenessContext(dpiContext uintptr) (ret uintptr) = user32.SetThreadDpiAwarenessContext

internal/win/zsyscall_windows.go

@@ -75,7 +75,7 @@ var (
 	procDispatchMessageW             = moduser32.NewProc("DispatchMessageW")
 	procEnableWindow                 = moduser32.NewProc("EnableWindow")
 	procEnumChildWindows             = moduser32.NewProc("EnumChildWindows")
-	procGetDlgCtrlID                 = moduser32.NewProc("GetDlgCtrlID")
+	procGetDlgItem                   = moduser32.NewProc("GetDlgItem")
 	procGetDpiForWindow              = moduser32.NewProc("GetDpiForWindow")
 	procGetMessageW                  = moduser32.NewProc("GetMessageW")
 	procGetSystemMetrics             = moduser32.NewProc("GetSystemMetrics")
@@ -90,6 +90,7 @@ var (
 	procRegisterClassExW             = moduser32.NewProc("RegisterClassExW")
 	procReleaseDC                    = moduser32.NewProc("ReleaseDC")
 	procSendMessageW                 = moduser32.NewProc("SendMessageW")
+	procSetDlgItemTextW              = moduser32.NewProc("SetDlgItemTextW")
 	procSetFocus                     = moduser32.NewProc("SetFocus")
 	procSetForegroundWindow          = moduser32.NewProc("SetForegroundWindow")
 	procSetThreadDpiAwarenessContext = moduser32.NewProc("SetThreadDpiAwarenessContext")
@@ -305,11 +306,6 @@ func EnableWindow(wnd HWND, enable bool) (ok bool) {
 	return
 }
 
-func EnumChildWindows(parent HWND, enumFunc uintptr, lparam unsafe.Pointer) {
-	syscall.Syscall(procEnumChildWindows.Addr(), 3, uintptr(parent), uintptr(enumFunc), uintptr(lparam))
-	return
-}
-
 func EnumWindows(enumFunc uintptr, lparam unsafe.Pointer) (err error) {
 	r1, _, e1 := syscall.Syscall(procEnumChildWindows.Addr(), 2, uintptr(enumFunc), uintptr(lparam), 0)
 	if r1 == 0 {
@@ -318,9 +314,12 @@ func EnumWindows(enumFunc uintptr, lparam unsafe.Pointer) (err error) {
 	return
 }
 
-func GetDlgCtrlID(wnd HWND) (ret int) {
+func GetDlgItem(dlg HWND, dlgItemID int) (ret HWND, err error) {
-	r0, _, _ := syscall.Syscall(procGetDlgCtrlID.Addr(), 1, uintptr(wnd), 0, 0)
+	r0, _, e1 := syscall.Syscall(procGetDlgItem.Addr(), 2, uintptr(dlg), uintptr(dlgItemID), 0)
-	ret = int(r0)
+	ret = HWND(r0)
+	if ret == 0 {
+		err = errnoErr(e1)
+	}
 	return
 }
 
@@ -356,7 +355,7 @@ func GetWindowRect(wnd HWND, cmdShow *RECT) (err error) {
 	return
 }
 
-func GetWindowTextLength(wnd HWND) (ret int, err error) {
+func getWindowTextLength(wnd HWND) (ret int, err error) {
 	r0, _, e1 := syscall.Syscall(procGetWindowTextLengthW.Addr(), 1, uintptr(wnd), 0, 0)
 	ret = int(r0)
 	if ret == 0 {
@@ -365,7 +364,7 @@ func GetWindowTextLength(wnd HWND) (ret int, err error) {
 	return
 }
 
-func GetWindowText(wnd HWND, str *uint16, maxCount int) (ret int, err error) {
+func getWindowText(wnd HWND, str *uint16, maxCount int) (ret int, err error) {
 	r0, _, e1 := syscall.Syscall(procGetWindowTextW.Addr(), 3, uintptr(wnd), uintptr(unsafe.Pointer(str)), uintptr(maxCount))
 	ret = int(r0)
 	if ret == 0 {
@@ -423,6 +422,14 @@ func SendMessage(wnd HWND, msg uint32, wparam uintptr, lparam uintptr) (ret uint
 	return
 }
 
+func SetDlgItemText(dlg HWND, dlgItemID int, str *uint16) (err error) {
+	r1, _, e1 := syscall.Syscall(procSetDlgItemTextW.Addr(), 3, uintptr(dlg), uintptr(dlgItemID), uintptr(unsafe.Pointer(str)))
+	if r1 == 0 {
+		err = errnoErr(e1)
+	}
+	return
+}
+
 func SetFocus(wnd HWND) (ret HWND, err error) {
 	r0, _, e1 := syscall.Syscall(procSetFocus.Addr(), 1, uintptr(wnd), 0, 0)
 	ret = HWND(r0)

msg_windows.go

@@ -2,8 +2,6 @@ package zenity
 
 import (
 	"context"
-	"syscall"
-	"unsafe"
 
 	"github.com/ncruces/zenity/internal/win"
 )
@@ -55,14 +53,11 @@ func message(kind messageKind, text string, opts options) error {
 	}
 
 	defer setup()()
-
+	unhook, err := hookMessageDialog(opts)
-	if opts.ctx != nil || opts.okLabel != nil || opts.cancelLabel != nil || opts.extraButton != nil || opts.icon != nil {
+	if err != nil {
-		unhook, err := hookMessageDialog(opts)
+		return err
-		if err != nil {
-			return err
-		}
-		defer unhook()
 	}
+	defer unhook()
 
 	var title *uint16
 	if opts.title != nil {
@@ -88,35 +83,27 @@ func message(kind messageKind, text string, opts options) error {
 }
 
 func hookMessageDialog(opts options) (unhook context.CancelFunc, err error) {
-	// TODO: use GetDlgItem, SetDlgItemText instead of EnumChildWindows.
+	var init func(wnd win.HWND)
-	return hookDialog(opts.ctx, opts.windowIcon, nil, func(wnd win.HWND) {
+	if opts.okLabel != nil || opts.cancelLabel != nil || opts.extraButton != nil || opts.icon != nil {
-		win.EnumChildWindows(wnd, syscall.NewCallback(hookMessageDialogCallback),
+		init = func(wnd win.HWND) {
-			unsafe.Pointer(&opts))
+			if opts.okLabel != nil {
-	})
+				win.SetDlgItemText(wnd, win.IDOK, strptr(*opts.okLabel))
-}
+				win.SetDlgItemText(wnd, win.IDYES, strptr(*opts.okLabel))
+			}
+			if opts.cancelLabel != nil {
+				win.SetDlgItemText(wnd, win.IDCANCEL, strptr(*opts.cancelLabel))
+			}
+			if opts.extraButton != nil {
+				win.SetDlgItemText(wnd, win.IDNO, strptr(*opts.extraButton))
+			}
 
-func hookMessageDialogCallback(wnd win.HWND, lparam *options) uintptr {
+			icon := getIcon(opts.icon)
-	ctl := win.GetDlgCtrlID(wnd)
+			if icon.handle != 0 {
-
+				defer icon.delete()
-	var text *string
+				ctl, _ := win.GetDlgItem(wnd, win.IDC_STATIC_OK)
-	switch ctl {
+				win.SendMessage(ctl, win.STM_SETICON, uintptr(icon.handle), 0)
-	case win.IDOK, win.IDYES:
+			}
-		text = lparam.okLabel
-	case win.IDCANCEL:
-		text = lparam.cancelLabel
-	case win.IDNO:
-		text = lparam.extraButton
-	}
-	if text != nil {
-		win.SetWindowText(wnd, strptr(*text))
-	}
-
-	if ctl == win.IDC_STATIC_OK {
-		icon := getIcon(lparam.icon)
-		if icon.handle != 0 {
-			defer icon.delete()
-			win.SendMessage(wnd, win.STM_SETICON, uintptr(icon.handle), 0)
 		}
 	}
-	return 1
+	return hookDialog(opts.ctx, opts.windowIcon, nil, init)
 }

pwd_windows.go

@@ -183,8 +183,8 @@ func passwordProc(wnd win.HWND, msg uint32, wparam uintptr, lparam *unsafe.Point
 		default:
 			return 1
 		case win.IDOK, win.IDYES:
-			dlg.usr = getWindowString(dlg.uEditCtl)
+			dlg.usr = win.GetWindowText(dlg.uEditCtl)
-			dlg.pwd = getWindowString(dlg.pEditCtl)
+			dlg.pwd = win.GetWindowText(dlg.pEditCtl)
 		case win.IDCANCEL:
 			dlg.err = ErrCanceled
 		case win.IDNO:

util_windows.go

@@ -79,6 +79,9 @@ func setupEnumCallback(wnd win.HWND, lparam *win.HWND) uintptr {
 }
 
 func hookDialog(ctx context.Context, icon any, title *string, init func(wnd win.HWND)) (unhook context.CancelFunc, err error) {
+	if ctx == nil && icon == nil && init == nil {
+		return func() {}, nil
+	}
 	if ctx != nil && ctx.Err() != nil {
 		return nil, ctx.Err()
 	}
@@ -314,13 +317,6 @@ func centerWindow(wnd win.HWND) {
 	win.SetWindowPos(wnd, 0, x/2, y/2, 0, 0, win.SWP_NOZORDER|win.SWP_NOSIZE)
 }
 
-func getWindowString(wnd win.HWND) string {
-	len, _ := win.GetWindowTextLength(wnd)
-	buf := make([]uint16, len+1)
-	win.GetWindowText(wnd, &buf[0], len+1)
-	return syscall.UTF16ToString(buf)
-}
-
 func registerClass(instance, icon win.Handle, proc uintptr) (*uint16, error) {
 	name := "WC_" + strconv.FormatUint(uint64(proc), 16)